   [{:name :md-icon-name     :required true  :default "md-add"        :type "string"     :description "the name of the icon. "}
    {:name :on-click         :required false                          :type "( ) -> nil" :description "function to call when the button is clicked"}
    {:name :size             :required false :default ":regular"      :type "keyword"    :description "One of :regular, :smaller or :larger."}
-   {:name :tooltip          :required false                          :type "string"     :description "show a popover-tooltip containing this text."}
+   {:name :tooltip          :required false                          :type "string | hiccup" :description "what to show in the tooltip."}
    {:name :tooltip-position :required false :default ":below-center" :type "keyword"    :description "position of the popover-tooltip. e.g. :right-below."}
    {:name :emphasise?       :required false :default false           :type "boolean"    :description "if true, use emphasised styling so the button really stands out."}
    {:name :disabled?        :required false :default false           :type "boolean"    :description "if true, the user can't click the button."}

  [{:name :md-icon-name     :required true  :default "md-add"        :type "string"     :description "the name of the icon."}
   {:name :on-click         :required false                          :type "( ) -> nil" :description "function to call when the button is clicked."}
   {:name :mouse-over-row?  :required false :default false           :type "boolean"    :description "true if the mouse is hovering over the row."}
   {:name :tooltip          :required false                          :type "string"     :description "show a popover-tooltip using this text."}
   {:name :tooltip-position :required false :default ":below-center" :type "keyword"    :description "position of the popover-tooltip. e.g. :right-below."}
   {:name :disabled?        :required false :default false           :type "boolean"    :description "if true, the user can't click the button."}
   {:name :class            :required false                          :type "string"     :description "CSS class names, space seperated."}

  [{:name :md-icon-name     :required true  :default "md-add"        :type "string"     :description [:span "the name of the icon."]}
   {:name :on-click         :required false                          :type "( ) -> nil" :description "function to call when button is clicked"}
   {:name :size             :required false :default ":regular"      :type "keyword"    :description "One of :regular, :smaller or :larger."}
   {:name :tooltip          :required false                          :type "string | hiccup" :description "what to show in the tooltip."}
   {:name :tooltip-position :required false :default ":below-center" :type "keyword"    :description "position of the popover-tooltip. e.g. :right-below."}
   {:name :emphasise?       :required false :default false           :type "boolean"    :description "if true, use emphasised styling so the button really stands out."}
   {:name :disabled?        :required false :default false           :type "boolean"    :description "if true, the user can't click the button."}
